This invention relates to examination devices of the kind used by physicians to examine the interiors of body cavities and/or the orifices thereof and to facilitate surgical operations within the body cavities. In particular the present invention is described with reference to an examination device for use in relation to the vagina.
There are a number of ways in which physicians routinely examine the interior of the vagina. One such method is to employ a known dilating speculum comprising a tubular array of two or more rigid, elongate leaves, which are inserted into the vagina of a patient and expanded in a radially outward direction to open the vagina for inspection. When prior known speculums have been used to admit pressurised fluid for expanding a body cavity having an external orifice, such as the vagina, it has been usual to tolerate the escape of some of the fluid, usually air but sometimes liquid, even though this is unpleasant for the operator and increases the messiness of the operation. Proposals to alleviate the disabilities flowing from the escape of fluid have included the use of inflatable sealing elements encircling a part of the tubular probe within the body cavity but near the orifice thereof. This has not always been effective and invariably obstructs the view of the cavity surface contacted by the sealing element. Furthermore, the provision of such sealing elements and the means to inflate them have materially increased the cost of the disposable, so called throw away, tubular probe.
Colposcopes are routinely employed by physicians to examine the interior of the vagina through such a speculum. Colposcopes typically comprise a binocular microscope and an illuminating unit which allows the physician to examine the vagina. In many instances the colposcope is a bulky and expensive instrument set on a stand at approximately 300 mm away from the vagina, and as a result of the magnification provided by the microscope the physician is able to conduct a close up examination. As the colposcope is bulky and requires a relatively large stand capable of supporting it, it is difficult for the physician to work in close to the area being examined, particularly when taking pap smears and/or conducting minor surgery.
Germany Patent Specification No. DE4404253 discloses an exploratory device which includes a sealing plug having feed through ducts for an instrument and connection ducts for a suction connection or an air supply connection to enable gas to pass into or out of the body cavity. A feature of the plug is the provision of an aspirator integral with the plug for controlled removal of gases from the body cavity being. With such an arrangement, sterilisation is difficult and an additional, inflatable seal is preferred which has the disadvantages to which reference has previously been made.
U.S. Pat. No. 3,817,251 discloses a cannula for laparoscopy which includes a cone shaped sleeve adapted to block the incisional gap. With this arrangement, the sleeve is formed of stainless steel or a chrome plated steel and is used for surgical treatment where an incision is made into the abdominal wall. This structure is totally unsuitable for use in examining the interiors of body cavities and would be difficult to seal against the cavity opening.
U.S. Pat. No. 4,258,721 relates to a hysteroscope which includes a cannula for insufflation of a fluid, such as carbon dioxide, inside the uterine cavity. The cannula is combined with an element which abuts the cervix of the uterus. However, the shape of the abutting element is such that a substantial part thereof is engaged within the opening thus preventing examination of the tissue adjacent thereto.
It is therefore desirable to provide an improved examination device which obviates at least some of the disadvantages of prior examination devices and which, in addition, is relatively simple and economical to manufacture and use.
It is also desirable to provide an examination device which is simple to use up close to a body cavity being examined, and through which biopsy samples may be obtained and surgery may be conducted with greater facility than heretofore.
In one aspect the present invention comprises an examination device for use in examining the interior of a body cavity, said device including an elongate tubular member having a first end and a second end, a hand piece having a bore there through, and a closure means including an eye-piece, the elongate tubular member being detachably fitted within the bore of the hand piece and the closure means being secured to the second end of the tubular member to provide a line of sight extending through the closure means and along the bore of the tubular ember, and the tubular member having a shield means which extends radially outwardly way from the tubular member for preventing contact of the hand piece and closure means with tissue surrounding the body cavity being examined.
In an embodiment of the invention, the shield means comprises an annular member removably engaged with the tubular probe to extend substantially radially therefrom. The diameter of the shield means is such that a front surface portion is able to contact tissue surrounding the opening of the body cavity being examined in such a way as to seal against the egress of fluid from the body cavity.
Preferably, the hand piece includes a light source from which light may be transmitted through the tubular probe, which, in this embodiment, is of a material capable of transmitting light.
In another embodiment the shield means is a cup or dome shaped member which, in use, is adapted to overlie and partially surround at least a part of the hand piece. The cup or dome shaped shield member has a base portion by which the shield member is engaged with the tubular probe. The base portion has an outer surface adapted to engage and seal with tissue surrounding the opening of the body cavity. One or more annular ribs or like surface deformations may be formed in the outer surface of the base portion to enhance the sealing with the surrounding tissue.
Embodiments of the invention may provide means for admission of a pressurised fluid into the bore of said tubular probe for expanding the body cavity. In such embodiments, the closure means is provided with a self-sealing aperture for the insertion through the tubular probe and into the expanded body cavity of surgical instruments, such as catheters, tissue sample extractors, cauterising devices and the like. The shield means of the present invention facilitates the use of such devices by reducing the escape of fluid from the expanded body cavity during the examination and subsequent procedure.
In a further embodiment of the present invention, the shield means comprises a disposable, annular shield sealingly engaged with the tubular probe and extending radially therefrom. The shield is configured and dimensioned to provide a surface portion of substantial area to contact an area of body tissue surrounding the orifice of the body cavity to be examined. The shield is formed of a resilient deformable material and may be provided with one or more annular ribs or the like to enhance sealing contact with the body tissue. The shield may be of disc shaped, dome or cup shaped or bell shaped so as to partially fit within the orifice of the body cavity whilst having a side wall which shields the hand piece. By forming the shield of a resilient, deformable material, use of the shield does not result in discomfort to the patient and provides a degree of movement of the tubular probe by an operator as the probe is directed towards different parts of the internal cavity surface to be examined or treated, without losing sealing efficiency of the shield. Further, the resilient, deformable shield is easily and quickly assembled with a tubular probe in a sealing manner and in a way which ensures that the shield is retained in place on the tubular probe and effects a fluid seal with the probe.
In one form of the invention, the tubular probe is provided with a circumferential abutment on an external surface thereof a predetermined distance from is first end. The shield, which has a substantially centrally located opening therein, is a sliding, interference fit with the first end of the tubular probe and abuts the circumferential abutment to locate the shield axially along the tubular probe and providing an increased sealing effect between the surfaces of the shield and the tubular probe. In a particular form of the invention, the shield is moulded from a closed cell, resilient plastics foam material or is cut or stamped or otherwise formed from a sheet of such material. A suitable synthetic plastics material includes polyethylene but may also include any other plastics material capable of forming a resilient closed cell body having smooth external surfaces which are impervious to gas or liquid penetration and which is resistant to chemical reaction with body fluids, sterilising fluids, antiseptics and the like. In an alternative arrangement, the shield may be formed of two or more materials, such as a relatively rigid backing piece having a resilient sealing layer associated therewith.